Are you thinking about creating an Amazon Web Services account for your business? Not sure where to start? In this course you’ll get an overview of the history of AWS and take a tour of their user interface.

I also had same issue with Optiplex 990. This model has structural issues. I had solved this issue temporaryly by opening the case and attach another SATA DVD and finish the installation. Opened a support case and they came and replaced it BUT new one also acted same way, even worse, as tray was not coming out. Next day we have noticed screws should be lose! Well thats obvious structural design issue.